1. Field of the Invention
The present invention relates to steam ovens. More specifically, the present invention relates to a steam oven for an aircraft used for heating and humidifying an in-flight meal to provide the in-flight meal.
2. Description of the Related Art
In such a type of steam oven, water dropped in a cook chamber is heated by an oven heater to generate steam, and, thus, to diffuse the steam in the cook chamber by a centrifugal fan, and, at the same time, generate a circulating flow, whereby food on a casserole placed in the cook chamber is heated and humidified.
Such a steam oven is designed to have a rectangular solid shape in consideration of ease of mounting on an aircraft. A food tray on which a casserole is placed can be freely inserted in and removed from the cook chamber through a door provided on the front surface of the rectangular solid cook chamber.
A plurality of food trays (for example, eight trays) are stacked in a portable rack, and about three to four casseroles can be placed on each food tray according to the size of the casseroles. The food tray is designed so that to provide in-flight service, a plurality of foods can be heated and humidified at one time.
Such a type of steam oven is disclosed in U.S. Pat. No. 5,209,941 and Japanese Patent Application Laid-Open No. 2003-227612.
In a steam oven for an aircraft used for heating in-flight meals, steam is diffused, and a centrifugal fan for generating a steam flow is rotated in the reverse direction for a certain time of a cooking period. Consequently, foods on casseroles on food trays in a rectangular solid cook chamber can be uniformly heated, and thus the occurrence of heating unevenness can be reliably prevented.
As described above, in the steam oven, a plurality of food trays on which casseroles are placed are placed in the rectangular solid cook chamber, and since the centrifugal fan rotating in the normal rotation direction rotates the steam flow, generated in the cook chamber, in the same direction, the steam flow is applied to only a part of the surface of food on each casserole. Thus, it is difficult to uniformly apply the steam to the entire surface of the food.
Further, the steam inevitably stays in the corners of the rectangular solid cook chamber. Each food tray and each casserole, on the upstream side of the steam flow, placed on the food tray are impinged on the steam flow rotating in the same direction to prevent the circulation of the steam flow. Consequently, the steam is not circulated around the casseroles on the downstream side, whereby some foods on the casseroles are not satisfactorily heated, and therefore, passengers may make complaints.
The present invention provides a steam oven for an aircraft, which can realize prevention of occurrence of heating unevenness. A centrifugal fan for generating a steam flow is rotated in the reverse direction for a certain time of a cooking period, whereby the stem flow in the cook chamber is significantly changed to be applied to the surface of each food that is less likely to receive the steam, and, at the same time, by virtue of the reverse rotation of the steam flow, the steam is forcibly circulated around steam staying portions generated in the corners of a rectangular solid cook chamber, racks, and food trays, whereby foods on casseroles placed near the steam staying portions can be uniformly heated.